Chapter 17, Problem 79A

Evaluate this statement: A low value for $K_{\text{eq}}$ means that both the forward and reverse reactions are occurring slowly.

Interpretation Introduction

Interpretation:

This is to be shown that the low equilibrium constant means slow forward and reverse reactions.

Concept introduction:

The equilibrium constant depends on the concentration of the reactants as well as the products.

Answer to Problem 79A

The given statement is somewhat correct because the low value of K_eq means that the concentration of both the reactants and products is somewhat comparable. But it does not mean that the reaction rates are slow. There is the possibility of both forward and reverse rates being high yet comparable.

Explanation of Solution

A low K_eq means that the concentrations of the reactants and the products are somewhat comparable which means that the rates of formation of products and the formation of reactants are also comparable but that does not necessarily mean that the rates are slow.

Conclusion

A low equilibrium constant does not necessarily mean a slow rate of forward or reverse reaction.